BOTANY OF TERRA ATJSTRALIS. 29 



the dilated, and in a few cases obscurely lobed, apex of 

 Avhich the sessile ovarium is placed. If this be a correct 

 view of the structure of Euphorbia, it may be expected that 

 the true filament or upper joint of what has commonly 

 been called filament, should, as in other plants, be produced 

 subsequent to the distinct formation of the anthera, which 

 consequently will be found at first sessile on the lower 

 joint or peduncle, after that has attained nearly its full 

 length ; and accordingly this proves to be the case in such 

 species as I have examined. Additional probability is given 

 to this view by the difference existing between the surfaces ps? 

 of the two joints in some species. I consider it, however, 

 as absolutely proved by an unpublished genus of this order, 

 having an involucrum nearly similar to that of Euphorbia, 

 and like it, inclosing several fasciculi of monandrous male 

 flowers, surrounding a single female ; but which, both at 

 the joint of the supposed filament, and at that by which 

 the ovarium is connected with its pedicellus, has an obvious 

 perianthium, regularly divided into lobes. 



UMBELLIEER^.* This order may be considered as 

 chiefly European, having its maximum in the temperate 

 climates of the northern hemisphere ; in the corresponding 

 southern parallels it is certainly much less frequent, and 

 within the tropics very few species have been observed. In 

 Terra Australis the Umbelliferse, including a few AraUse, 

 which belong at least to the same natural class, exceed 50 

 species. The greater part of these are found in the principal 

 parallel, in which also those genera deviating most remark- 

 ably from the usual structure of the order occur. The most 

 singular of these is Adinotus of Labillardiere,^ which difi'ers 

 from the whole order in having a single ovulum in the un- 

 impregnated ovarium. A second genus, which I shall here- 

 after publish with the name of Leucolena, is worthy of 

 notice on account of the great apparent difierences of inflo- 

 rescence existing amongst its species ; which agree in habit, 



' hs. gen. 218. , , n orr 



2 Nov. RoU.pl. spec. '\,p. 67, t. 92. Eriocaha, Smith exot. hot. 2, p. 67. 



